A mainstay of professional western kitchens, the Petty knife is a small general-purpose knife used for peeling, shaping, and slicing fruits and vegetables, chopping herbs, and making garnishes. The petty knife is the knife for smaller jobs that are done on a cutting board. Think slicing shallots, cutting herbs and boning smaller cuts of meat, fish or birds. Petty knives are an essential tool for bartenders who serve fresh fruit garnishes.